A hockey puck with a mass of 0.16 kg travels at a velocity of 40 m/s toward a goalkeeper. The goalkeeper has a mass of 120 kg and is at rest. Assuming a closed system, find the total momentum of the goalkeeper and puck after the puck is caught by the goalkeeper. In 3-4 sentences, identify the object with the greater momentum after the puck is caught and explain your reasoning.(4 points)
Instead of giving the straight up answer can you also explain the reasoning? Please Help me :(
total momentum does not change, assuming the goalie starts to slide away unhindered by friction.
Naturally, though, the velocity of the goalie would probably be zero, as he digs in his skates.
To solve this problem, we can use the principle of conservation of momentum. According to this principle, in a closed system with no external forces acting on it, the total momentum before an event is equal to the total momentum after the event.
Before the puck is caught, the total momentum of the system is given by the sum of the momentum of the puck and the momentum of the goalkeeper. The momentum of an object is calculated by multiplying its mass by its velocity.
After the puck is caught, the system is still closed, meaning no external forces have acted on it. Therefore, the total momentum of the system remains the same.
Comparing the masses and velocities, we can see that the mass of the hockey puck is relatively low compared to the mass of the goalkeeper. However, the velocity of the hockey puck is significantly higher than the velocity of the goalkeeper initially at rest.
Since momentum takes into account both mass and velocity, even though the mass of the goalkeeper is greater, the velocity of the puck is high enough to compensate and potentially result in a greater momentum after the catch. Therefore, the object with the greater momentum after the puck is caught is likely to be the hockey puck, assuming no other external forces are involved.
To find the total momentum of the goalkeeper and puck after the puck is caught, we can use the conservation of momentum principle, which states that the total momentum before an event is equal to the total momentum after the event. The initial momentum of the puck can be calculated by multiplying its mass (0.16 kg) by its velocity (40 m/s), giving us 6.4 kg m/s. Since the goalkeeper is at rest initially, their initial momentum is 0 kg m/s. After the puck is caught, the total momentum of the system will still be conserved and thus will be equal to the initial momentum.
To identify the object with the greater momentum after the puck is caught, we need to compare the initial momentum of the puck and the initial momentum of the goalkeeper. Since the initial momentum of the puck is 6.4 kg m/s and the initial momentum of the goalkeeper is 0 kg m/s, we can conclude that the puck has the greater momentum. This is because momentum is a product of mass and velocity, and the puck's mass is significantly smaller than the goalkeeper's mass, resulting in a higher momentum due to the higher velocity.